Improvement in molds for castings



`Be it known `that I, WILLIAM MURDocx, of Jersey City, inthe countyof Hudson, State ,provedModef of `Making Castings in Iron suchas cannonballs, shell, dumb-bells, clock, scale, and sash-weights, Ste.; and I do hereby declare that the following is a full and exact, "description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

In these drawings, Figure l represents a e section in line X X `of Fig. 2. Fig. 2 represents a section in lineY Y of Fig. 1. Fig3 represents a plan view.

`Letter B represents the mold to which the j e shaft is attached; letter C, the-mold which is 4driven by the screw; B', `the shaft; B", the `balance-wheel; C', the screw; C, theserew` wheel; a, the gate of` the mold; b, spacegin- `sideoi moldwor form of casting; c, raised screw; F, l, caps with end of screw in position;

G, pins and corresponding holes.

The nature of my` invention consists in an improved `cast-ironmold` in two parts, the inside of whichY is a space, b, ofthe size and form of the eastingto be made,with a gate, a, l for the metal cut from theoutside to the space b of the molds, one-half `infeach` mold around this gate ct andthe form of the casting orspace b, and on eachmold a raised edge, c, is to be made of one-quarter of an inch inwidth and t one-sixteenth of` an inch in thickness, (more or less.)` Said edges e must be fitted closely `together mold to moldyfTheobject of this raised edge e is to preventthe molds, when 4 l hot and expanded,fr`om"openi`ng n'ext to the f form of castingfor space b, and this overcomes perhaps the greatest objection to the use of cast-ironmolds.` (Ordinarily, molds are faced t together entirely across their meeting surface, e and, of necessity, being very thick, their inneredges being incontact with the molten metal, heat and expand one from the other, while their outside edges, being removed from the directfcause of heat, and being exposed to the air, remain comparatively cool and still closed, thus causing a serious imperfection in l every casting madeafter the first.)

My moldsfare hung `horizontally in an iron of New J ersey-,have invented a new and lm- Letter A represents the frame of the mold. y

edges; D, shaft-boxes; E, stationary nut of A the inside of the casting.

" wLLiMMURDoc-x, or JERSEY CITY, New .Inns-EY.

'.IMPROVEMENT |N""|v|oLDs FOR CASTINGS.

i Specification forming part of Letters Patent No. 35,2118, vdated'May 13, A1862.

frame, A, of suflicient `length as to allow one mold C to be drawn away from the other mold B, i till the casting drops. On theouter edge of the face of one mold B are two or more pins, G, with corresponding holes G in the other mold C, and on the outside of the pin-mold B, opposite the form of casting b, is a shaft, B', passingthrough a set of boxes, D, on the frame A. Upon the extreme end of this shaft B is hung a balance-wheel, B, of suiiicient weight to balance the molds. Gn the outside of the other mold C, corresponding to where the shaft B is on the opposite mold B, is a hole or countersink. Into this hole is admitted the end of a screw, C', with a collar one-half of an inch from the point. Vhen the point of the screw C is in its position a cap, F, in halves with a half-hole in each, these holes are placed around the collar of the screw G and the caps F screwed to the mold C, thus preventing the withdrawal ofthe screw G from the mold C. On this end of the frame A,.cor Iresponding with the shaft-boxes D on the opposite end, is a' stationary nut of screw `E, and on the outer end of this screw G is a fly-wheel, C", Vfor driving it. The agency of this screw C is manifold. It closes and opens the molds with ease and rapidity, and holds them iirmly together while pouring the metal. It allows the molds to be worked at great heat, for by it the party working is subject to no inconvenient heat. It discharges the castings with dispatch, thus relieving the molds and improving the nature of the casting made. By its agency the molds can be poured continually without fear of melting or becoming too hot to work conveniently.

The mode of casting is-viz., the molds being screwed together with the gate a uppermost, into them the metal poured, the wheel B on the shaft B revolved slowly and regularly while the metal is in a molten state, (the neck or smallest part of the gate a chills instantly, preventing the metal from running from the molds while revo1ving,) and until the outside of the casting is set, thus throwing the heaviest and solid parts of the metal to the surface, and all dross, dirt, shrinkage, &c.,.to When the outside rof the casting has become firm or set, the screw O is run back and the casting dropped as soon as possible, so as to prevent the molds from becoming` unnecessarily hot, and allowing,` the casting to cool from :t White heitt in the air. By so doing the Castings become perfectly soft when cool. y

In the making of shell, n core-tube print must be ent between the molds, half in catch, and opposite the gate a, and the core-tube iitted nicely into it. Vhen the molds are screwed together, the core will be held in n very correct and firm position. In castings that require it screws, Wires, chills, cores of various kinds, &c., can be set in like manner.

Having now fully described my invention,

what I clain'i therein as new, and desire to se- WILLIAM MURDOCK.

Vitn esses:

J. B. Bonnin, Crus. W. EvANs. 

